1. Field of the Invention
The present invention relates to a method for making nanocrystal and, particularly, to a method for making metal oxide nanocrystal.
2. Discussion of Related Art
Nanocrystals are defined as nanometer sized, single crystalline fragments of the corresponding bulk crystals. The term “nanometer-sized” is typically used to refer to particles with an approximate size range between about 1 nanometer (nm) to about 1000 nm in diameter. More typically, “nanometer-sized” refers to an approximate size rang between about 1 nm-100 nm in diameter. Metal oxide nanocrystals play important roles in many different branches of science and technology, such as catalyzer material, lithium cell, and electronic and optical devices.
Synthesis of high quality metal oxide nanocrystals has a critical role in this very active field. The conventional method includes metal organic salt reduction method, hydro-thermal method, and sol-gel method. However, the metal organic salt reduction method requires the use of metal precursors, which are extremely toxic, expensive, and unstable at room temperature, the hydro-thermal method is restricted by product apparatus, and the sol-gel method is not good at control of the size and the size distribution of nanocrystal.
However, there is ongoing demand for a simple, timesaving, low toxic, easy for mass product method for making metal oxide nanocrystal with good size control, narrow size distribution, and good crystallinity.